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Let’s talk about snakes! What do you know about them? I had to do some homework on this subject since there are no snakes in the office! The vets were all talking about snakes after one of the horses got a snake bite right on the tip of his nose! Seems unfair, but from what I hear, horses like to put their noses into everyone’s business!

In Virginia there are ~ 35 types of snakes but only 3 are venomous (Copperheads, Timber Rattlesnakes and Cottonmouths.) Only 2 of the venomous types show up in Northern Virginia.

Nothern Copperheadwww.wildlifeofct.com

Northern Copperheads (Agkistrodon contortrix mokeson) are our main culprit for snake bites as they are pretty common. Copperheads can be up to 48 inches in length and they like to hang out anywhere that there are rodents (barns, wood piles, sawdust piles.) They typically have a copper colored head with hourglass patterns of brown on a lighter brown or grey background. They also have dark spots on the sides of their belly (but who really wants to get close enough to see a snake’s belly?!?) Younger copperheads often have a sulfur yellow tail tip.

Timber Rattlesnakewww.virginiaherpetologicalsociety.com

Rarely, the Timber Rattlesnakes (Crotalus horridus horridus)make it into our area. They can be up to 60 inches in length! Timber rattlesnakes have 2 color phases. In the black phase, the head and front 1/3 of the body is black and they have black saddles and incomplete chevrons that are hard to see on the dark background of the body. The yellow phase is much more distinct with the saddles and chevrons being easily seen. A third venomous snake, the canebrake rattlesnake is a variation of the timber rattlesnake and is typically limited to Southern Virginia.

The quick ways of identifying venomous snakes in Northern Virginia are: (1) The venomous snakes in NOVA are pit vipers, meaning that they have a heat-sensing pit between their eye and their nostril. (2) Our venomous snakes have a single row of scales along the underside of their tail. Nonvenomous snakes have a double row of scales on the underside of their tail. (3) Our venomous snakes have an elliptical pupil, while their nonvenomous counterparts have round pupils. (4) Venomous snakes tend to have a more triangular head than nonvenomous snakes.

It is important to remember that these differences are a general rule only. I know that I don’t want to get close enough to a snake to see whether they are venomous or not!

The best rule: DON’T HANDLE SNAKES! This doesn’t mean that snakes are not a good part of our ecosystem. Having snakes around the barn will keep your rodent population down. If you don’t want snakes around, the best plan of action is to make your barn/yard/home uninviting. Keep things clean and tidy so there aren’t good hiding places. You should also make sure grain and treats are protected from rodents.

According to the Center for Human-Wildlife Conflict Resolution snakes are classified as a non-game protected species. You can look at their site http://www.humanwildlife.org/ for the legalities of snake removal/management. As with all wildlife, non-lethal control measures should be exhausted before any lethal measures are used. You can also look at the Virginia Department of Game and Inland Fisheries website for information about snakes and other wildlife: https://www.dgif.virginia.gov/wildlife/nuisance/snakes/.

So what actually happens with a venomous snake bite? Well, the venom of the Copperhead and Timber Rattlesnake is typically hemotoxic and destroys blood and lymph cells. Horses typically get bitten on the nose as they tend to use them to investigate.

photo by Dr. Jessica Williamson

Occasionally they get bitten on the lower limb or body. Adult copperhead bites can be serious but they tend to inject less venom than the younger ones (typical that adults are more in control of their venom than the juveniles!). Rattlesnake bites tend to be much more serious than those of the copperhead.

photo by Dr. Jennifer French

Any venomous snake bite can be life threatening to your horse! If your horse is bitten by a venomous snake it is considered an emergency situation. Why? Well, if a horse gets bitten on the nose, the subsequent swelling can block their airway leading to death or the venom can cause systemic shock or anaphylactic shock which can lead to sudden death. Care may include anti- inflammatories, antibiotics for secondary infection, IV fluids and possibly a tracheostomy to maintain an airway. Sometimes the swelling and infection is so bad that surgical intervention is needed to treat/remove the affected tissue. Some horses must be euthanized due to secondary complications even when they survive the initial envenomation.

What should you do if you suspect that your horse has been bitten by a snake? (1) Call us immediately, (2) Confine your horse and keep him quiet, (3) identify the snake if you can do so without endangering yourself.

Prognosis for a snakebite if you’re a horse? Guarded to good. Only about 1/2 of the horses bitten receive enough venom to put them at risk of life threatening reactions but there is no way to know at the time of the bite how much venom was injected.

Snakes are much maligned and we need to remember that they play an important role in our ecosystem and they deserve respect. Snakes are actually pretty cool critters! Unfortunately sometimes our interactions have severe consequences.